You must be yolking! Study finds an egg a day increases risk of stroke death ...

A new study claims eating an egg a day dramatically raises your risk of a heart attack or a stroke.

Many leading cardiologists say the study, which reignites a fierce and controversial debate over eggs, is the most rigorous ever published.

Assessing data on 30,000 people, the researchers found that people with dangerously high cholesterol were more likely to have eggs - crucially: with yolks included - as a stalwart of their diet.

Tallying it up, they conclude that a daily egg increases the risk of heart disease by 18 percent, and the risk of premature death from a stroke by 17 percent.

But others warn we shouldn't all leap to cut eggs from our diet: there are significant caveats to the study, which is based on old, self-reported data.

Crucially, after the researchers adjusted for total cholesterol intake (from red meat, cigarettes, and other sources) the egg connection flopped.

Experts on all sides largely agree that the study shows we should keep an eye on cholesterol - but it's unclear that cutting out eggs is the best way to do that.

Northwestern University researchers reviewed data on 30,000 people and found those who ate more eggs had a higher risk of stroke death. But critics say the findings are flawed

The egg-heart disease debate has been thriving for decades.

A handful of studies have looked into it - and many researchers have done 'reviews' of those same studies - coming up with all kinds of results.

They have found eggs are transformatively good for you, deadly for you, and everything in between.

The key issue is that nutrition studies are hard to carry out: it is very difficult to control what someone is eating, and to know that they followed your direction - particularly if it is over a long time.

Short of conducting the study in a prison, a nursing home, or the Big Brother house, there is a large margin for error.

The new study, published today in the Journal for the American Medical Association, was hailed in an accompanying editorial as 'far more comprehensive' than previous studies, 'with enough data to make a strong statement that eggs and overall dietary cholesterol intake remain important in affecting the risk of [heart disease] and more so the risk of all-cause mortality.'

But Christopher Labos, MD, a cardiologist at McGill University, told DailyMail.com he is less convinced.

First, the research does not offer anything new.

'This was a meta-analysis of six different cohorts summarized together,' Dr Labos said.

'The statistical analysis they used is certainly more complex than in previous cases, but at the end of the day you're just synthesizing everything that's already there. It